With current technologies, an image scanning apparatus often includes a document tray, a document discharge tray, a feeding section, an image scanning section, and an information processing section. The feeding section feeds the original document on the document tray to the image scanning section along the feeding path. After scanning the image information on the document by the image scanning section, the feeding section continues feeding the document to the document discharge tray. The scanned image information is processed by the information processing section and duplicated to a new paper after processing.
However, currently, the image formed on the new paper may have a vertical black line. As shown in FIG. 12, the direction indicated by the arrow in the figure is the paper feeding direction. During the actual operation, vertical black lines may appear on the paper, that is, the vertical black lines may appear in one or more locations of ‘a’, ‘b’, ‘c’, and ‘e’. The figure shows only examples of the location, length, thickness, and the number of the vertical black lines. That is, the location, length, thickness and the number of the appearing vertical black lines may be random. This vertical black line is not what the user desires. Electrostatic charging of the image scanning device or of the original document may cause such problem. In the industry, the impact of static electricity on the scanning process is usually eliminated by using a static brush disposed on the feeding path and/or the frame. However, waste paper scraps or other dust may be generated during the feeding process of the original document, and the above problem may still occur if the above paper scraps or dust accumulates in the scanning position. In the industry, the paper scraps or dust is often periodically cleaned by a professional in order to solve the above problem.
Thus, such a way of using static brush cannot solve the problem of vertical black lines caused by paper scraps or dust, while the regular cleaning by professionals is costly and it is also difficult to effectively solve the vertical black line problem. Therefore, a new solution is urgently needed for the above problem.